Anywhere you go, air pollution is big business. Big business in its production a la factories, power plants and automobiles. Big business in the expenditures on ameliorating controls and prevention measures. And big business in the size of the national health care bill we get when the business of pollution dominates the business of pollution control and prevention.

Still, the debate between those that favor economic gain over green considerations (a false choice in many regards, as I’ve written about here and here) and those that argue environmental health spurs economic health rages on. Two papers published last week add a bit of fuel to the debate.

Just a few days ago, the New York Timesreported that “[o]nly three of the 74 Chinese cities monitored by the central government managed to meet official minimum standards for air quality.” Can China turn that around? A new study, by Deliang Tang of the Mailman School of Public Health at Columbia University and colleagues published last week in the journal Plos One, suggests that opportunities for significant improvement abound.

The authorslooked at the developmental patterns of two cohorts of children — one born before and one born “after a highly polluting, coal-fired power plant in Tongliang County, China had ceased operation” because it had been such a huge source of pollution. For each cohort, at the time of their birth, their umbilical cord blood was analyzed for molecular biomarkers of exposure to polycyclic aromatic hydrocarbons (PAHs) related to DNA damage2 and brain-derived neurotrophic factor (BDNF), a key protein for brain development.

At age 2, the children were tested for developmental milestones. The results showed that the second cohort born after the coal plant closed had less PAH exposure and better developmental scores.

The bottom line: With the air quality as bad as it is in China, almost any action — like closing down a single power plant — can reap significant health benefits.

In the United States: Incremental Progress Continues

Lest we get too smug, it bears noting that some towns and cities right here in the United States face similar problems from local factories and power plants. (More examples here and here.)

Still, we’ve made a lot of progress here and Americans living in metropolitan areas usually find themselves breathing air that is relatively clean by international standards.

And then in 1997 — it was like déjà vu all over again. New epidemiological data showed persistent health effects from ozone and fine (smaller than 2.5 micrometers in diameter) particulates at lower and lower concentrations. EPA responded with stricter air quality standards for ozone and a new standard for fine particulates [pdf]. These standards set many areas that had been in or had just reached attainment into non-attainment, requiring that they develop long-term plans to get back on track. See for example: this paper and this paper.

Not surprising, there was significant opposition [pdf] to EPA’s new standards. Some argued that the epidemiological evidence justifying the new standards was weak, others that compliance would be prohibitively expensive. Some even expressed skepticism that the standards, being so close to ambient background concentrations, could ever be met. (Some of these objections may sound familiar — they were played out just a few years ago when EPA was considering lowering the ozone standard once again. In this case, the Obama administration blinked and the standard was not changed.)

A paper published last week in the Journal of the Air and Waste Management Association by Daniel Cohan and Ran Chen of Rice University suggests that at least some of those concerns were unfounded. (Full disclosure: Daniel Cohan is a former Ph.D. student of mine.) The authors analyzed air quality data from parts of the country that did not meet the new fine particle air quality standard in the late 1990s and so were required to develop plans to meet the standard by 2009. The authors reported that

“Of the 23 eastern U.S. regions considered here, all but one achieved the 15 [micrograms/cubic meter] μg/m3 standard by 2009, and the other achieved it the following year, with downward trends sustained in subsequent years.”

So meeting those new standards was feasible and the pollution controls implemented were effective in meeting those standards.

But the real proof of the value of an air quality abatement program is in data showing improvements in public health and/or ecosystem function. That was relatively easy in the case of the plant closure in China, but when you get to the low levels of pollution we’re currently at and the incremental nature of the air quality improvements, it can be a challenge. It requires detailed statistical analyses of years of epidemiological data to tease out the connection between changes in air quality and health outcomes from the noise of a host of confounding factors.

So while the Chinese get to see the benefits of their air quality program almost immediately, we’ve got to live with some uncertainty. That’s the price we pay for the decades of work we’ve put into cleaning up our air. Well worth the bargain.

2 Comments

Contaminants in the air with a higher than normal level.
Is long enough to cause harm to humans, animals, plants or assets.

Hank Roberts

Apr 7, 2014

Hm, I suppose if the US had managed to export union-organizing, the IWW, and the Clean Air Act regulations — rather than exporting business deals based on 19th-Century dirty cheap technology — then China would have fewer dollars, less environmental damage, and a much more powerful position in the world today.

Very clever, these Americans. They got the USSR to collapse with an arms race, and got China into deep and unnecessary trouble by paying them to do themselves in.